Lifting-jack



L. E. JOHNSON.

LIFTING JACK.

APPLICATION FILED JULY 6, 191B- j 336,9()6 Patented Apr. 13, 1920.,

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L. E. JOHNSON.

LIFTING JACK.

APPLICATION FILED JULYG, 191a.

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LAWRENCE E. JOHNSON, OF MELROSE, MASSACHUSETTS, ASSIGNOR T0 MATTIE S.

. JOHNSON, OF MELROSE. MASSACHUSETTS.

LIFTING-J'ACK.

Specification of Letters Patent.

Patented Apr. 13, 1920.

To all ze/mm it may concern lle it known that I. llaivnnxcn E. Jouxsex. a citizen of the United States of A1nerica. and a resident of Melrose, county of Middlesex, and State of lVIassachusctts. have invented certain new and useful Improvements in Lifting-Jacks. of which the following is a specification.

This invention relates to lifting jacks, and has for its object the production of a. device of this character in which the vertically moving member may be readily elevated and retainedin elevated position until re.- leased by the operator to permit the lowering of the load at a speed automatically con trolled by a governor.

This invention consists primarily in connecting the lateral shaft of the elevating mechanism to a manually controlled brake mechanism coacting with an automatic governor mechanism whereby the device may be set for any desired speed of lowering ,and

any tendency to exceed said predetermined speed will be overcome automatically.

The invention further consists in certain novel features of construction and arrangement of parts which will be readily understood by reference to the description of the drawings and to the claims hereinafter given.

For the purpose of illustrating the invention. one preferred form thereof is illustrated in the drawings. this form having been found to give satisfactory and reliable results, although it is to be understood that the 'arious instrumentalities of which the invention consists can be variously arranged and organized. and that the invention is not limited to the precise arrangement and or-- ganization of the instrumentalities as herein shown and described, except as required by the scope of the appended claims.

Of the drawings:

Figure 1 represents a vertical section of a lifting jack embodying the principles of the present invention.

Fig. '2 represents a vertical section of a portion of the same on line 2, 2 on Fig. 1

looking in the direction of the arrow.

Fig. 3 represents a vertical section on line 3. 3 on Fig. 1 looking in the direction of the arrow.

Fig. 4 represents a vertical section on line 4, 4 on Fig. 2, and

Fig. 5 represents a detail in elevation to be hereinafter described.

Similar characters designate like parts throughout the several figures of the drawings.

In the drawings 10 is a stationary member provided with a supporting base 11.

In the upper end of the stationary n1emher 10 is positioned a non-revoluble nut 12 to which is threaded the screw 13 provided at its lower end with a shouldered nut 14 to limit the upward movement of said screw.

The upper end of said screw has keyed or otherwise secured thereto a bevel gear 15 meshing with a bevel gear 16 forming a part of the lifting mechanism.

Surrounding the hub of the gear 15 is a fiber washer 17 and an annular plate 18, the latter having formed in its upper face a groove 19 in which rest a plurality of antifriction members 20 on which-rests another annular plate 21 having a groove 22 in its under face into which the anti-friction members 20 project.

The upper reduced end 23 of the screw 13 is adapted to freely revolve in the plate 21 which has superimposed thereon the closure 24 of a cylinder 25, the lower end of which surrounds the stationary member 10 and is movable vertically thereon.

From the side of said cylinder 25 projects a rectangular casing 26 having a closing plate 27 provided with bearings 28 and 29 to receive the lateral revoluble shaft 30 and the non-revoluble shaft 31.

The shaft 30 is preferably formed integral with the bevel gear 16 as shown in the drawlugs and said shaft 30 has mounted thereon a ratchet 32. which ratchet is revoluble with said shaft 30 and said gear 16.

Loosely mounted upon the shaft 30, between the ratchet 32 and the bearing 28, is a gear 33 having ivoted thereto, at 34 and 35, pawls 36 and 3 one of which is always in engagement with the ratchet 32.

Projecting from the face of the gear 33 are two pins 38 adapted to limit the outward movement of said pawls 36 and 37 about their pivots 34 and 35.

On the outer end of the shaft 30 is an operating mechanism 39 which may be of any well known construction.

By means of this operating mechanism 39 the gears 16 and 15 may be rotated to turn to be raised until t e nut 14 comes into contact with the face 40 of the stationary member 10, thus limiting the upward movement of said cylinder 25. I

When the cylinder 25 is being raised, the ratchet 32 will be rotated in the direction of the arrow at onFig. 3 of the drawings without imparting rotary movement to the loosely mounted gear 33.,

When the load is being lowered the ratchet 32 will be rotated in the direction opposite to that indicated by .arrow a on Fig. 3 of the-drawings and, one of the pawls 36 and 37 being in engagement with said ratchet 32, rotary movement will be 1mparted to the loosely mounted gear 33 on the shaft 30. D

The gear 33 meshes with the pinion 41 secured to the hub of a on -shaped member 43 mounted upon and revo uble about the axis A of the non-revoluble shaft 31 and preferably rovided on its eriphery with gear teeth. ne end of this s aft 31 is positioned in the beari 29 and the opposite end is sup orted in the racket 44 secured to the inner ace of the closing plate 27.

The non-revoluble shaft 31 is locked in position by means of clamping nut 45.

The cup-shaped member 43 is provided with a cylindrical recess 46 in which is positioned a non-revoluble member 47 which is prevented from being rotated by means of the pin 48 extending into the same from the bracket 44.

Throughout the specification, the cup-- shaped member 43 will hereinafter bedesignated as a gear although it must be understood that under certain conditions the peripheral teeth thereof may be dispensed with and other means provided for actuating the pinion 58.

The non-revoluble member 47 has one strai ht edge 49 from which'project two parafiel pins 50.

Between the straight edge 49'and the inner wall of the cylindrical recess 46 is interposed a brake member 51 supported by the pins 50 and movable outwardly thereon in a direction radial to the axis of the shaft 31.

The second gear 43 is normally prevented from rotating about the periphery of the non-revoluble member 47 and the brake i 52 is moved outwardly the member 51 can v move inwardlytoward the member 47.

The cone-shaped wedge 52 is secured to a threaded member 53 extendin through the closing plate 27 and provide on its outer end wit an operating lever 54 by which said threaded member may be rotated about its axis to force the cone-shaped wedge 52 inwardly and cause the brake member 51. to impinge upon the inner wall of the recess 46 in the gear 43.

When the threaded member 53 is moved outwardly the wedge 52 will be moved therewith so that the brake member 51 ma move toward the non-revoluble member 4 and thus release its grip upon the inner wall of the recess 46 in the gear 43.

The bracket 44 is provided with a cylindrical chamber 55 in which are positioned two friction disks 56 having axially positioned therein a floating pin orsupport 57 on which is mounted a pinion 58 meshing with the second gear 43.

The pin 57 has no other support than the disks 56 and consequently can have a slight anovement about the axis of the non-revoluble shaft 31. I v

The disks 56 are fitted to the chamber 55 so that under normal conditions they may be rotated freely in said chamber when the pinion 58 is rotated by the gear 43 about the axis of the pin 57. These disks 56 are of greater diameter than the pinion 58 and are of sufficient weight to materially assist the rotation of said pinion when rotary movement is being imparted to said pinion subsequent to the initial starting operation.

It is obvious that the disks 56 and pinion 58 are driven upon the pin 57 so that they will always rotate together. When the threaded member 53 has been adjusted to cause the wedge 52 to force the brake member 51 into contact with the inner wall of the recess 46 so that a predetermined speed of the lowering of the load is provided for, the disks 56 will rotate freely in the chamber 55, but as soon as the load causes the cylinder 25 to move downwardly faster than the desired predetermined speed the quicker rotation of the gear 43 will cause the floating pin 57 to be moved slightly about the axis of the shaft 31 and force the peripheries of the disks 56 into such frictional. contact with portions of the wall of the chamber 55 as to retard the rotation of the gear 43 and thus assure its rotation at a speed previously determined.

It is obvious therefore, that'by means of the rotation of the threaded member 53 any desired speed of lowering the load may be determined upon and by means of the friction governor 56, 56, 57 the lowering of the load at this predetermined speed will be antomatically controlled.

In order to make the device absolutely one end of a helical spring 61, the opposite end of which is secured to a pin (32 in the (over plate 27.

The spring (31 acting upon the arm 60 I turns the member 53 so that the wedge 52 will be normally in its inner position forcingthe brake member 51-1nto gripping contact with the lnner wall of the chamber 46-.

When it is desired to lower the load the operator moves the lever 5-f downwardly thereby moving the wedge 52 outwardly and releasingthe grip of the brake member 51 from the wall of chamber 46.

'hen the machine is not in use the brake anember 51, in gripping contact with the wall of the recess 46, will prevent the rotation of the gear 43.

When the lever 54 is depressed-the wedge 52 will be moved outwardly thereby decreasing the frictional contact between the brake member 51 and the wall of the recess 46 and thus permitting said brake member 51 to act as a speed controller.

It is obvious that the speed may be regulated by the degree'of frictionalcontact between the brake member 51'and the wall of the recess 46. r

The load may be lowered as long as. the operator keeps the lever 54 depressed but as soon as he releases said lever' the spring 61 will immediately act to rotate the member 53 sufficiently to force the wedge 52 inwardly and causethe brake 51 to act thereby preventing further rotation of the gear 43 and any-further lowering of the load until the lever 54 is again depressed.

The lever 54 is protected by a rib 63 partially inclosing said lever the-object of this rib 63 being to prevent said lever 54 from being accidentally hit and releasing the brakes unintentionally.

It is believed that the operation and the many advantages of the present invention will be fully understood without further deseription.

Having thus described my invention, I claim:

1. The combination of an operating shaft: a casing therefor; a ratchet revoluble with said shaft; a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a cnp-shaped-member revoluble with said pinion; a non-revoluble member inclosed within said cup-shaped member; means for expanding said non-revoluble member: and means on the casing for preventing the rotating. of said non-revoluble member.

2. The combination of an operating shaft; a casing therefor; a ratchet revoluble with said shaft; a gear loosely mounted on said shaft; a pawl on said gear, enga ing said ratchet; a pinion meshing with said gear; a cup-shaped member revoluble with said pinion; a non-revoluble member inclosed Within said cup-shaped member; means on the casing for preventin r the rotating of said non-revoluble mem er; and manually operated means extending through the casing for expanding said non-revoluble member.

The combination of an operating shaft; a casing therefor; a ratchet revoluble with said shaft; a gear looselymounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a cup-shaped member revoluble with said pinion; a non-revoluble member inclosed within said cup-shaped member; means on the casing for preventing the rotating of said non-revoluble member; and means operable from the outside of the easing for creating a friction between said cupshaped member and said non-revoluble member.

4. The combination of an operating shaft; a casing therefor; a ratchet revoluble with said shaft; a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a cup-shaped member revoluble with said pinion; a non-revoluble two-part member inclosed within said cup-shaped member; means on the casing for preventing the rotating of said non-revoluble member; and

means operable from the outside of the easing for expanding said non-revoluble member.

5. The combination of an operating shaft; a casing therefor; a ratchet revoluble with said shaft; :1 gear loosely mounted on said. shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a cup-shaped member revoluble with said pinion; a non-revoluble member inclosed within said cup-shaped member; means on the casing for preventing the rotating of said non-revoluble member: a brake member movable relatively to said non-revoluble member; and means interposed between said non-revoluble member and said brake member for forcing said brake member into frictional contact with said cup-shaped member.

6 The combination of an operating shaft: a casing therefor; a ratchet revoluble with said shaft: a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshlng with said non-revoluble member; and means interposed between said non-revoluble member and said brake member for. forcing said brake member radially into frictional contact with said cup-shaped member.

7. The combination of an operating shaft; a casing therefor; a ratchet revoluble with said shaft; a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshingwith said gear; a cup-shaped member revoluble with said pinion; a non-revoluble member inclosed within said cup-shaped member; means on the casing for preventing the rotating of said non-revoluble member; a brake member movable relatively to said non-revoluble member; and manually controlled means interposed between said nonrevoluble member and said brake member and operable from the outside of the casing for forcing said brake member into frictional contact with said cup-shapedmember. Y

8. The combination of an operating shaft; a casin therefor; a ratchet revoluble with said' liaft; a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a cup-shaped member revoluble with said pinion; a non-revoluble member inclosed within said cup-shaped member; means on the casing for preventing the rotating of' said non-revoluble member; a brake member movable relatively to said non-revoluble member; a movable wedge interposed between said non-revoluble member and said brake member for forcing said brake member into frictional contact with said cup-shaped member; and means on the outside of the casing for actuating said wedge.

9. The combination of an operatingshaft; a casing therefor; a ratchet revoluble with said shaft; a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear;.a cup-shaped memberrevoluble with said pinion; a non-revoluble member 1nclosed within said -cup-shaped member; means on the casing for preventing the rotating of said non-revoluble member; a

- brake member movable relatively to said non-revoluble member; a movable wedge interposed between said non-revoluble member and said brake member for forcing said brake member into frictional contact with said cup-shaped member; a threaded member for imparting inward movement to said wedge; and means on the outside of the casing for rotating said threaded'member.

10. The combination of an operating shaft; a ratchet revoluble with said shaft; a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a cup-shaped member revoluble with said pinion; a non-revoand. means interposed between said non revoluble member and said .brake memberfor forcing said brake member into frictional contact with said cup-shaped member. 11. The combination of an operating shaft; a ratchet revoluble therewith; a ear loosely mounted on said shaft; a paw on said gear, engaging said ratchet; a pinion meshing with said gear; a second gear revoluble with said p1n1on;' a second pinion meshing with said second ear; 8. non-revoluble member provided with a cylindrical chamber; and a friction disk revoluble with said second pinion within said chamber and adapted to be moved into contact within the wall thereof.

12. The combination of an operating shaft; a ratchet revoluble therewith; a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with 831d gear; a second gear revoluble with said pinion; a second pinion meshing with said second gear; a cylindrical member extending from said second pinion; a disk on said cylindrical member; and a non-revoluble member provided with a chamber into which said disk fits.

13. The combination of an operating shaft; a ratchet revoluble therewith; a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a second gear revoluble with said plnion; a second pinion meshing with said second gear; a non-revoluble member provided with a cylindrical chamber; two disks fitted to said chamber on opposite sides of said second pinion; and a pin extending through and revoluble with said disks and second pinion.

14. The combination of an operating shaft; a ratchet revoluble therewith; a gear loosely mounted on said shaft; a pawl on said gear engaging said ratchet; a pinion meshing with said gear; a second gear revoluble with said pinion; a second pinion meshing with said second gear; a non-revoluble member provided with a cylindrical chamber; two disks fitted to said chamber on opposite sides of said second pinion; and a floating pin extending through and revoluble with said disks and second pinion.

15. The combination of an operating shaft; a ratchet revoluble therewith: a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a second gear revoluble with said pinion; a second pinion meshing with said second gear; a non-revoluble member provided with a cylindrical chamber; two disks fitted to said chamber on opposite sides of said second pinion; and a pin extending through and revoluble with said disks and second pinion and supported only by said disks.

16. The combination of an operating shaft; a ratchet revoluble therewith; a gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a second gear revoluble with said pinion; a second pinion meshing with said second gear; a non-revoluble member provided chamber; two disks fitted to said chamber on opposite sides of said second pinion; and a pin extendin through and revoluble with said disks an second pinion and having slight movement about the axis of said sec- 0nd gear.

17. The combination of an operating shaft; a ratchet revoluble with said shaft; a

gear loosely mounted on said shaft; a pawl on said gear, engaging said ratchet; a pinion meshing with said gear, a cup-shaped member revoluble with said pinion; manually controlled means for regulating the speed of lowering-of the load and positioned within-said cup-shaped member; and an independent mechanism coacting with and actuated by said pinion for preventing said pinion rotating faster than the predetermined speed for lowering.

18. The combination of an operating shaft; a casin therefor; a ratchet revoluble with said shaft; a member loosely mounted on said shaft; a pawl on said member, engaging said ratchet; a cup-shaped member adapted to be revolved by said. member during the lowering of the load; a non-revoluble member inclosed within said cup-shaped member; means on the casing for preventing the rotating of said non-revoluble member; a brake member movable relatively to said non-revoluble member; and means interposed between said non-revoluble member and said brake member operable from the outside of the casing for forcing said brake member into frictional contact with said cup-shaped member.

19. The combination of an operating shaft; a casing therefor; a ratchet revoluble with said shaft; a member loosely mounted on said shaft; a pawl onsaid member, engaging said ratchet; a cupshaped member adapted to be revolved by said member during the lowering of the load; a non-revoluble member inclosed within said cup-shaped member; means on the casing for preventing the rotating of said non-revoluble member; a brake member movable relatively to said non-revoluble member; and means interposed between said non-revoluble member and said brake member for forcing said brake member radially into frictional contact with said cup-shaped member.-

with a cylindrical said 20. The combination of an operating shaft; a casing therefor; a ratchet revoluble with said shaft; .a. member loosely mounted on said shaft; a pawl on said member, engaging said ratchet; a pinion meshing with said gear; a cup-shaped member adapted to be revolved by said member during the lowering of the load; a non-revoluble member inclosed within said cup-shaped member; means on the casing for preventing the rotating of said non-revoluble member; a brake member movable relatively to non-revoluble member; and manually controlled means interposed between, said non-revoluble member and said brake member for forcing said brake member into frictional contact with said cup-shaped member.

21. The combination of an" operating shaft; a casing therefor; a ratchet revoluble with said shaft; a member loosely mounted on said shaft; a pawl on said member, engaging said ratchet; a cup- ,shaped member adapted to be revolved by said member during the lowering of the load; a non-revoluble member inclosed within said cup-shaped member; means on the casing for preventing the rotating of said 'non-revoluble member; a brake member movable relatively to said non-revoluble member; a movable wedge interposed between said non-revoluble member and said brake member for forcing said brake memher into frictional contact with said cupshaped member; and means on the outside of said casing for actuating said wedge.

22. The combination of an operating shaft; a casing therefor; a ratchet revoluble therewith; a member loosely mounted on said shaft; a pawl on said member, engaging said ratchet; and a friction disk governor confined within said casing and adapted to berotated by said member during the lowering of the load and adapted to be bodily moved so that its periphery will be forced into frictional contact with the wall of said casing to automatically prevent said member rotating faster than a predetermined speed.

23. The combination of an operating shaft; aratchet revoluble therewith; a member loosely mounted on said shaft; a pawl on said member engaging said ratchet; a non-revoluble member provided with a cylindrical chamber; and a disk within said chamber adapted to be rotated by said shaft member during the lowering of the load and forced into frictional contact'with the wall of said chamber when said member commences to rotate faster than a predetermined speed.

24. The combination of an operating shaft; a ratchet revolving therewith; a member loosely mounted on said shaft; a pawl on said member engaging said ratchet;

a non-revoluble member provided with a cylindrical chamber; a disk titted to said chamber adapted to be rotated by said shaft member during the lowering of the load; and a floating support for said disk whereby said disk may be forced into frictional contact with the wall of said chamber when said member commences to rotate faster than a predetermined speed.

25. The combination of an operating shaft: a casing therefor: a ratchet revoluble with said shaft: a member loosely mounted on said shaft: a pawl on said member. engaging said ratchet: a cup-shaped member adapted to be revolved by said shaft member during the lowering of the load: a non-revoluble member inclosed within said cup-shaped member: means on the casing for preventing the rotating of said non-revoluble memberra brake member also within said cup-shaped member and movable. relatively to said non-revoluble member; a wedge interposed between said inclosed members and normally forcing said brake member into contact with said cup-shaped member; and means for moving said wedge outwardly to release said brake member.

26. The combination of an operating shaft; a ratchet revoluble with said shaft: a member loosely mounted on said shaft; a pawl on said member, engaging said ratchet; a'cup-shaped member adapted to be revolved by said shaft member during the lowering of the load: a non-revoluble member inclosed within said cup-shaped memher; a brake member also within said cupshaped member and movable relatively to said non-revoluble member: a wedge interposed between said inclosed members and normally forcing said brake member into contact with said' cup-shaped member: means for moving said wedge outwardly to release said brake member: and automatic means for returning said wedge to its normal position to effect the operation of said brake.

27. The combination of an operating shaft; a ratchet revoluble with said shaft: a member loosely mounted on said shaft; a pawl on said member, engaging said ratchet:

a cup-shaped member adapted to be re volved by said shaft member during the lowering of the load; a non-revoluble member inclosed within said cup-shaped member; a brake member also within said cup-shaped member and movable relatively to said nonrevoluble member; a wedge interposed between said inclosed members and normally forcing said brake member into contact with said cup-shaped member; means for moving said wedge outwardly to release said brake member; and a spring for returning said wedge to its normal position to effect the operation of said brake.

28. The combination of an operating shaft; a ratchet revoluble with said shaft; a member loosely mounted on said shaft; a pawl on said member, engaging said ratchet; a cup-shaped member adapted to be revolved by said shaft member during the lowering of the load; a non-revoluble member inclosed within said cup-shaped memshaft; a ratchet revoluble with said shaft; a

member loosely mounted on said shaft; a pawl on said member, engaging said ratchet; a cup-shaped member adapted to be revolved by said shaft member during the lowering of the load; a non-revoluble member inclosed within said cup-shaped member; a brake'member also within said cupshaped member and movable relatively to said non-revoluble member; a wedge interposed between said inclosed members and normally forcing said brake member into contact with said cup-shaped member; and an operating lever for moving said wedge outwardly to release said brake member; and a protecting rib partiallysurrounding said lever.

30. The combination of an operating shaft; a ratchet revoluble with said shaft; a member loosely mounted on said shaft; a

pawl on said member engaging said ratchet;

a cup-shaped member adapted to be revolved by said shaft member during the lowering of the load; a non-revoluble member inclosed within said cup-shaped member; a brake member also within said cupshaped member and movable relatively to said non-revoluble member; a wedge interposed between said inclosed members and normally forcing said brake member into contact with said cup-shaped member; a rotatable member movable with said wedge; and provided with a portion threaded to a fixed part; an arm secured to the inner end of said rotatable member and a fixed part; and an operating lever on the outer end of said rotatable member.

31.- The combination of an operating shaft; a ratchet revoluble therewith; a gear loosely mounted on said shaft; a pawl on said ear, engaging said ratchet; a pinion mes ing with said gear; asecond gear revoluble with said pinion; a second pinion meshing with said second gear; a non-revoluble member provided with a cylindrical chamber in which said second pinion is positioned; a pin extending through and revolublewith said second pinion: and two disks of greater diameter than said second pinion and disposed on opposite sides thereof. said disks being secured to the projecting ends of said pin with their peripheries fitted to said cylindrical chamber.

32. The combination of an operating shaft; a ratchet revoluble therewith; a gear loosely mounted on said shaft: a pawl on said gear, engaging said ratchet; a pinion meshing with said gear; a second gear revoluble with said pinion; a second pinion meshing with said second gear; a nonrevoluble member provided with a cylindrical chamber in which said second pinion is positioned; a pin extending through and revoluble with said second pinion; and two weighted disks of greater diameter than said second pinion and disposed on opposite sides thereof, said disks being secured to the projecting ends of said pin with their peripheries fitted to said cylindrical chamber. Signed by me at Boston, Mass, this 3rd day of July, 1918.

LAWVRENCE E. JOHNSON. lVitnesses:

WALTER E. LOMBARD, NATHAN C. LOMBARD. 

